Metallic fastener



H. ROSENBERG METALLIC FASTENER July 7 1925.

Filed June 26 1922 fiyl/zmz Jame/z Jay 93 J I binations and arrangements of Patented July 7, 1925.

UNITED STATES PATENT OFFICE,"

To all whom it ma concern:

Be it known that HEYMAN ROSENBERG, a citizen of the United States, residing at New York, in the county of Bronx and State of New York, have invented certain others skilled in the art to which it appertains to make and use the same.

This invention relates to improvements in metallic fastening apparatus, and more particularly to such as is adapted for connecting together two pieces of metal or for anchorage in a piece of metal, with functions substantially equivalent to that of a rivet but without the necessity for the swaging of the entering end of the connecting device.

Among the objects in view are the reduction in the expense of production of such devices; the increase of efficiency; and the savingof labor.

With these and other objects in view,

95 as will in part hereinafter become apparent and in part be stated, the invention comprises certain novel constructions, com- (parts as subsequently specified and claime In the accompanying drawings, Figure -1 is a view 1n side elevation of a device embodying the features of the present invention, the structure being shown ona magnified scale so far as the average commercial article is concerned.

Figure 2 is an enlarged, detail, fragmentary, transverse sectlon taken on the plane indicated by line 2-2 of Figure 1 of the device as applied in use.

Figure 3 is a similar vertical section taken on the plane of line 3 3 of Figure 2. Figure 4is a view similar to Figure 3 taken on a plane spaced angularly of the device from the plane of Figure 3, as indicated by line 4-4 of Figure 1. v

The present invention relates to that type of devlces set forth in my United States Letters Patent No. 1,482,151, dated January 29, 1924, and the structure involved herein I designate a drive screw or a drive pin because of its adaptability to be drlven' in place by blows from a hammer notwithstanding the fact that parts of the device are cutting their way through parts of the Application filed June 26, 1922. Serial No. 570,912.

metal engaged and causing the metal to flowts to positions interlocking with such par Broad claims for anchorage devices of the character herein disclosed and characterized by outstanding projections, such as beads or threads or the like, on a body are presented in my (appending application, Serial No. 688,423, filed January 25, 1924, covering improvements in anchorage devices.

In the drawings, 1 indicates the body of the drive screw or (gain having a head 2 and. a series of threa s 3 of relatively high pitch extending from the head to points adacent the lower end of the body, the said lower end being left preferably smooth to form a pilot 4. The angularity of threads 3 1s suscept1ble of variation, and, in fact, maybe reduced substantially to the pointof zero, so that said threads may be cons dered and properly described as ribs. The pilot 4., as clearly seen in Figures'3 and 4, 1s of slightly lar er diameter than that of those portions 0 threads or ribs 3, but is of less diameter than the distance from the extreme outer edge of one thread 3 to the extreme outer edge of a diametrically opposite portion of another thread 3, stand beyond the lines of the cylinder described by the pilot 4. The number of threads 3 cm loyed is susceptible of some variation and should be great enough to insure a clogging action of metal between.

the threads after the pin has been driven into place and when stress is placed on the pin tending to withdraw it. That number of threads is preferably employed which leaves a space between threads slightly greater than the thickness of the base of any particular thread, and by the base is meant the place of jointure of the thread with the body 1, that is the thickest part of the thread. The threads or ribs 3 are characterized by not being continuous, that is, by being interrupted, made up of a series of sections, each section spaced from the next a distance referably equal approximately to one-hal the length of any section, and all of the sections being preferably of the same length. Of

course, the len e spaces correspondingly so that the threads 3 outeach being same diameter as the metal, indicated varied or the length of the sections may be increased ordecreased and the spaces in-.

creased ordecreased either regularly or irregularly, it being one of the im ortant features of the present invention t at the sections of threads shall be so arranged as to present terminal places or sh0ulders at the upper ends of the several sections which are adapted to' be somewhat overlapped by the flowing metal of the engaged work.

In practice, when a sheet or plate of metal, or other work, is to be engaged by the improved drive pin, an aperture, indicated at 5 in Figures 3 and 4, is formed in at 6 in said figures, the said aperture 5 being of substantially the the pilot 4 so as to allow the pilot to fit snugly and slide therein. The pilot is introduced into the aperture, and the head 2 is struck by a hammer, whereupon the lower ends of the threads 3 begin to cut their way into the metal of the device 6, the threads being hardened, as hereinafter described. When the pin 1 has been driven to its final position, the parts will have assumed the condition indicated in Figures 2, 3 and 4, wherein the metal of work 6 has flowed, as shown in Figure 4, to a position overhanging, at 6, the upper end of the shown section of thread 3, and at the same time, as seen in Figures 2 and 3-, the metal of the work 6 will have flowed to a position overhanging at 6" the shoulder 4 formed by the upper end of the pilot 4. When the parts are thus interlocked, it will 'be obvious that the drive pin may not be withdrawn. J

The drive pin is initially constructed preferably of soft metal, and when completed structurally, the'pin is subjected to a casehardening process such as the cyaniding or other well known case-hardening operations; whereby the threads, ribs, or lateral projections are hardened sufiiciently for cuttin their way in the material through which the pin is driven. It is to be understood, of course, that the case-hardening operation, while hardening the surface of the body and head of the pm, is not carried out for that purpose primarily, it being essential that the interrupted threads or ribs be hardened regardless of the other parts. The case-hardening operation, therefore, is emploved as the least expensive, uickest, and easiest means to the end desire It should also be understood that the terms hard" and hardened as employed throughout this specification and claims is intended to designate that degree of hardness enabling the ribs or threads to enter metal, such as soft iron or soft steel, substantially without injury to the ribs.

What I claim is:

1. A drive pin comprising a body having a pilot and interrupted hardened threads outstanding from the body beyond the lines of the pilot, the pilot being of larger diameter than that of those portions of the body between threads. 1

2. A drive pin comprising a body having interrupted hardened threads ofrelatively high pitch, the space between threads being equal approximately to the area of the base of a thread.

3. A drive pin comprising a body having outstanding projections s aoed about the body and also spaced longltudinally of the body, the body being formed with a smooth pilot portion at its entering end, said pilot being of a diameter greater than that of those portions of the body between the projections.

4. In metallic work, forming a recess in the work substantially equal in transverse area to the transverse area of the fastener, the fastener having interrupted hardened threads, and

driving the body along and within the recess for causing the threads to sever the material of the work and cause it" to flow to points in the rear of parts of the projections.

5. In the art of anchoring a fastener in metallic work, forming a recess in the work, of a transverse area equal substantially to the transverse area of the body of the fastener, the fastener having high-pitched hardened threads, and driving the fastener along and within the recess for causing the metal of the work to flow between the threads for clogging and interrupting withdrawal of the fastener.

6. In the art of anchoring a fastener in metallic work, forming a recess in the work of a transverse area equal substantially to the transverse area of the pilot of the fastener, the fastener havin high-pitched hardened threads on its b y, and a pilot outstanding from the body a less distance than the outstanding distance of the threads,

and driving the fastener along and within the recess for causing the metal to be severed and caused to flow by the threads to a position overhanging the pilot.

7. In the art of anchoring a fastener in metallic work, forming a recess in the work of a transverse area equal substantially to the transverse area of the pilot of the fastener, the fastener havin high-pitched hardened threads on its bo y, and a pilot outstanding from the body a less distance than the-outstanding distance of the threads, and driving the fastener along and within the recess for causing the metal to be severed and caused to flow by the threads to a position overhanging the pilot, and also clog substantially equal in transverse area to the position en aging the interlocking means transverse area of the fastener the fastener carried by t e fastener. 1

having a hardened rib extendln along its In testimony whereof Lafiix my signature body, and means for interlockm the rib in presence of two witnesses.

5 and material of the work, and driving the HEYMAN ROSENBERG.

body alon and within the recess for caus- Witnesses: ing the rib to enter the material of the Josnrn A. HUKLE,

work and cause such material to flow to a G. BALLEN; 

